Hi Carlos,
The IP analogy was only to point out that it's by design that one requires IP addresses to communicate. In the same way, it's by design that one must use WWPNs to communicate over an FC network. That's how FC was designed. That's it.
And configuring a boot target is really only unique or special to the booting host and the storage array, not the FC network itself. The network continues to perform FLOGIs and PLOGIs, continues to allocate FCIDs, continues to check zoning configuration to verify who can talk to who, continues to pass on LUN IDs regardless of whether they're boot LUNs or not. The fabric operation doesn't change whether we're talking about boot targets, data targets, or tape targets.
Multipathing is also unique to hosts. The fabric design should ensure multiple available paths so multipathing works, sure, but MPIO is a host-side feature and not fabric-specific, per se. Since multipathing won't necessarily be up and running, we configure host HBAs for primary and secondary boot paths. Again, nothing special regarding the fabric.
Boot from SAN is unique to hosts (and arrays) and not the fabric. The fabric acts like the universe - it's just there regardless of what we're doing here on Earth. The fabric is just there, regardless of whether we're booting from SAN. It will enable us to log in and it will enforce our zoning, whether at boot time or when accessing data. From there, it's all on the host and array to agree on boot LUN configuration.
I hope that helps a bit more.
All the best,
Mike
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Mike Brown
VMware, Cisco Data Center, and NetApp dude
Consulting Engineer
Twitter: @VirtuallyMikeB
Blog: http://VirtuallyMikeBrown.com
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